Researchers at Aarhus University in Denmark analyzed 225,626 tracks from 985 Spotify playlists that relate to sleep. The group then used the audio streaming platform’s software to compare sleep songs and general music.
Sleep music tends to be quieter and slower and features acoustic instruments. But according to their findings shared in journal PLOS One, a substantial amount of diversity was present among some sleep music in six categories.
Authors of the study said they “investigated the characteristics of music used for sleep and found that even though sleep music, in general, is softer, slower, instrumental and more often played on acoustic instruments than other music, the music people use for sleep displays a large variation, including music characterized by high energy and tempo.”
While three categories included songs with typical sleep music, the other categories featured louder and more energetic music. Some of the tracks were popular songs like “Dynamite” by K-pop group BTS and “lovely” by Billie Eilish and Khalid.
“The study can both inform the clinical use of music and advance our understanding of how music is used to regulate human behavior in everyday life,” the team behind the study added.
Although the researchers theorize that the higher energy songs could relax people due to familiarity, they said additional research would be needed to identify why people choose that specific type of music. In all, the study found there is no “one-size-fits-all” for the music people listen to when they fall asleep.
This article was originally published by The Hollywood Reporter.